全文获取类型
收费全文 | 20462篇 |
免费 | 1911篇 |
国内免费 | 608篇 |
专业分类
耳鼻咽喉 | 112篇 |
儿科学 | 153篇 |
妇产科学 | 97篇 |
基础医学 | 1157篇 |
口腔科学 | 1009篇 |
临床医学 | 1731篇 |
内科学 | 1587篇 |
皮肤病学 | 313篇 |
神经病学 | 655篇 |
特种医学 | 891篇 |
外科学 | 1460篇 |
综合类 | 3288篇 |
一般理论 | 3篇 |
预防医学 | 3292篇 |
眼科学 | 157篇 |
药学 | 4449篇 |
26篇 | |
中国医学 | 2286篇 |
肿瘤学 | 315篇 |
出版年
2024年 | 11篇 |
2023年 | 346篇 |
2022年 | 488篇 |
2021年 | 740篇 |
2020年 | 853篇 |
2019年 | 723篇 |
2018年 | 692篇 |
2017年 | 765篇 |
2016年 | 765篇 |
2015年 | 807篇 |
2014年 | 1381篇 |
2013年 | 1949篇 |
2012年 | 1401篇 |
2011年 | 1476篇 |
2010年 | 1113篇 |
2009年 | 1100篇 |
2008年 | 1150篇 |
2007年 | 1086篇 |
2006年 | 950篇 |
2005年 | 829篇 |
2004年 | 639篇 |
2003年 | 553篇 |
2002年 | 492篇 |
2001年 | 402篇 |
2000年 | 337篇 |
1999年 | 248篇 |
1998年 | 197篇 |
1997年 | 206篇 |
1996年 | 146篇 |
1995年 | 140篇 |
1994年 | 125篇 |
1993年 | 136篇 |
1992年 | 94篇 |
1991年 | 82篇 |
1990年 | 78篇 |
1989年 | 67篇 |
1988年 | 68篇 |
1987年 | 64篇 |
1986年 | 50篇 |
1985年 | 48篇 |
1984年 | 34篇 |
1983年 | 28篇 |
1982年 | 31篇 |
1981年 | 19篇 |
1980年 | 22篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 10篇 |
1976年 | 7篇 |
1975年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Edwin van der Pol Joshua A. Welsh Rienk Nieuwland 《Journal of thrombosis and haemostasis》2022,20(1):245-251
The Extracellular Vesicle Flow Cytometry Working Group ( http://www.evflowcytometry.org ) is formed by members of the International Society for Extracellular Vesicles (ISEV), the International Society for Advancement of Cytometry (ISAC), and the International Society on Thrombosis and Haemostasis (ISTH). This working group of flow cytometry experts develops guidelines for best practices regarding flow cytometry detection of extracellular vesicles. To improve rigor and standardization, this working group published a framework outlining the minimal information to report about a flow cytometry experiment on extracellular vesicles (MIFlowCyt-EV) in the Journal of Extracellular Vesicles, the ISEV journal, in 2020. In parallel, an article explaining MIFlowCyt-EV was published in Cytometry Part A, one of the ISAC journals, and now will be introduced to the ISTH as an SSC Communication in the Journal of Thrombosis and Haemostasis. The goal of this SSC Communication is to explain why flow cytometry is becoming the instrument of choice to characterize single extracellular vesicles, the obstacles that have been identified and (mostly) overcome by developing procedures to calibrate flow cytometers, and the relevance of reporting minimal information to improve reliability and reproducibility of experiments in which flow cytometers are used for characterization of extracellular vesicles. 相似文献
3.
《Journal of the American Medical Directors Association》2022,23(3):379-386.e3
ObjectivesPreclinical and clinical studies indicate a role for MLC901 (NeuroAiD II) in Alzheimer's disease (AD). The primary aim was to investigate its safety as add-on therapy to standard treatment and the secondary aims its effect on cognition and slowing disease progression.DesignRandomized double-blind placebo-controlled delayed-start study.Setting and ParticipantPatients with mild to moderate probable AD by NINCDS-ADRDA criteria, stable on acetylcholinesterase inhibitors or memantine (n = 125), were randomized to receive MLC901 (early starters) or placebo (delayed starters) for 6 months, followed by a further 6 months when all patients received MLC901, in a delayed-start design (clinical trial registration: ClinicalTrials.gov, NCT03038035).MethodsThe primary outcome measure was occurrence of serious adverse events (SAEs) at 6 months. Secondary outcomes included the Alzheimer's Disease Assessment Scale–Cognitive subscale (ADAS-Cog) and other assessment scales.ResultsThere was no significant difference in the risk of SAEs between early and delayed starters at month (M) 6 (22.6% vs 27.0%, risk difference ?4.4%, 90% CI –16.9% to 8.3%). Similarly, there was no significant difference in the risk of adverse events and the occurrence of stroke or vascular events between early and delayed starters throughout the 12-month study period. Early starters did not differ significantly on ADAS-Cog from delayed starters at M6 [mean difference (MD) ?1.0, 95% CI –3.3 to 1.3] and M12 (MD –2.35, 95% CI –5.45 to 0.74) on intention-to-treat analysis. Other cognitive assessment scales did not show significant differences.Conclusions and ImplicationsThis study of 125 persons with dementia found no evidence of a significant increase in adverse events between MLC901 and placebo, thus providing support for further studies on both efficacy and safety. Analyses suggest the potential of MLC901 in slowing down AD progression, but this requires further confirmation in larger and longer studies using biomarkers for AD. 相似文献
4.
5.
【目的】 总结科技期刊封面设计流程管理模式并探讨其中的相关问题,为同行提供经验借鉴。【方法】 从版面、设计风格等方面对科技期刊封面图片的特征进行归纳。以中国激光杂志社期刊封面为例,总结封面设计流程管理模式,探讨封面设计过程中的相关问题。【结果】 期刊应对封面的主题策划、生产流程、版权保护等方面进行有效的流程管理。此外,就封面设置及风格、元素文化、版权意识、与设计公司合作等问题进行思考总结。【结论】 科技期刊可通过合理的封面设计流程,将科技与艺术融合,更准确地传播前沿科技成果,并弘扬中国传统文化。 相似文献
6.
目的优选超声靶向微泡破坏(UTMD)技术介导载基因靶向纳米泡(T-NB)爆破的条件。方法采用薄膜水化法制备纳米泡,以生物素-亲和素-生物素连接方法制备pAd-AAV-9/miRNA-1 T-NB,观察其基本理化性质。基于机械指数(0.6、0.9、1.2、1.5)、T-NB溶液浓度(10^(5)/ml、10^(6)/ml、10^(7)/ml、10^(8)/ml)及辐照时间(30、45、60、120 s)设计三因素四水平正交实验,评价不同超声辐照参数对T-NB溶液信号强度的影响。结果pAd-AAV-9/miRNA-1 T-NB溶液为乳白色混悬液,浓度(0.74±0.10)×10^(8)/ml;T-NB为大小相近的球形,平均粒径(443.97±12.84)nm,平均电位(-7.33±0.09)mV。在不同辐照条件下,T-NB溶液的信号强度不同。机械指数、T-NB浓度及辐照时间均可显著影响信号强度(P均<0.05)。影响T-NB爆破的因素依次为机械指数、T-NB溶液浓度及辐照时间,机械指数0.6、T-NB浓度10^(6)/ml、辐照时间120 s为其最优组合。结论机械指数0.6、T-NB溶液浓度10^(6)/ml、辐照时间120 s为UTMD技术载基因T-NB的最优爆破条件。 相似文献
7.
《Vaccine》2022,40(31):4105-4115
The etiologic agents of visceral leishmaniasis are Leishmania infantum and Leishmania donovani. Despite the variety of drugs available to treat leishmaniasis, most lead to serious adverse effects, and resistance to these drugs has been reported. Currently, no leishmaniasis vaccine is available for humans. That is why the group developed transgenic L. infantum promastigote lines, which express toxic proteins after differentiation into amastigotes. That is why group developed the pFL-AMA plasmid and transfected it into L. Infantum promastigotes. This plasmid was expressed only in the amastigote form of the parasite. Sequences encoding toxic proteins (active bovine trypsin and egg avidin) were inserted in this plasmid, and the transfected parasites died after the differentiation process. In this study, two immunization protocols were performed in BALB/c mice: prime and prime-boost immunization prior to challenge with the wild-type L. infantum (WT). The parasite burdens in the spleen, liver, and bone marrow were evaluated to verify immunological protection. Histopathological analysis of the spleen and liver and the humoral immune response were also performed. The data showed that the parasite burden was reduced in prime-boosted mice in the spleen, liver, and bone marrow, indicating that mice immunized with two doses of the transfected parasites were satisfactorily protected. High levels of IgG, IgG1, and IgG2a antibodies were observed, as well as the presence of anti-inflammatory cytokine Interleukine-10 and pro-inflammatory cytokine Tumor Necrosis Factor-α (TNF-α) and Interferon-γ (IFN – γ) suggesting a Th1/Th2 mix response, in addition to the presence of multinucleated giant cells in the spleen and lymphocyte infiltration in the liver. Therefore, L. infantum transfected with a toxic plasmid is an excellent vaccine candidate against visceral leishmaniasis and the application of a boost before the challenge promotes greater protection against WT L. infantum infection. 相似文献
8.
目的 调查医院感染预防与控制课程设计中医学生的教育需求及教师的课程设计建议。方法 采用问卷调查全国5个地区10所医学院校师生的医院感染预防与控制教育需求和课程设计意见,参考塔巴目标模式课程设计步骤,论证课程设计方案。结果 584名学生中,仅11.8%(69名)的学生认为当前医院感染预防与控制教育能完全满足其需求,需求得分居前四位的为手卫生、消毒灭菌隔离、医院感染概论和职业防护。352名教师中,72.7%(256名)建议设必修课;86.4%(304名)选择总学时8~24学时,12.5%(44名)选择24学时以上,被调查教师建议10个章节学时平均总和为19.5;需重点掌握13项、熟悉9项知识和技能;86.4%(304名)教师建议理论与见习学时比为1 ∶0.5及以上;53.4%(188名)教师建议采取理论大课+小组见习(含技能操作)+线上学习的形式;63.7%(224名)教师建议师资团队由医院感染管理科+感染病科+护理部教师共同组成。结论 当前医学生的医院感染预防与控制教育远未完全满足需求,单独开课很有必要,建议设置16~24学时必修课,理论联系实践,多学科师资实施多元化教学,按照必修课考核。 相似文献
9.
《Drug discovery today》2022,27(1):82-101
WNT/β-catenin signaling orchestrates various physiological processes, including embryonic development, growth, tissue homeostasis, and regeneration. Abnormal WNT/β-catenin signaling is associated with various cancers and its inhibition has shown effective antitumor responses. In this review, we discuss the pathway, potential targets for the development of WNT/β-catenin inhibitors, available inhibitors, and their specific molecular interactions with the target proteins. We also discuss inhibitors that are in clinical trials and describe potential new avenues for therapeutically targeting the WNT/β-catenin pathway. Furthermore, we introduce emerging strategies, including artificial intelligence (AI)-assisted tools and technology-based actionable approaches, to translate WNT/β-catenin inhibitors to the clinic for cancer therapy. 相似文献
10.
目的 了解公立医院医务人员新型冠状病毒肺炎防护相关知识、态度和行为的现状,并探讨公立医院在现有人员配置的基础上提升医务人员公共卫生综合素质的方法,以期提升医院整体公共卫生应急处置能力。方法 抽取石家庄三家公立医院158名医务人员作为研究对象,采用问卷调查法对医务人员进行新冠肺炎防护相关知信行现状调查,采用单因素方差分析对影响医务人员新冠肺炎防护相关知识、态度及行为的因素进行分析。结果 医务人员新冠肺炎防护知识平均得分为(28.64±7.91)分;态度平均得分为(16.92±1.76)分;行为平均得分为(16.81±1.79)分,单因素方差分析显示护理专业人员知识得分比临床专业高;态度得分中公共卫生等相关科室及临床科室得分高于其他科室,公共卫生专业人员比护理专业及临床专业高;行为得分中临床科室人员明显高于其他科室,其他职称系列得分明显低于医师、护师和技师。结论 医务人员新冠肺炎防护相关知识水平有待提高,态度和行为水平较好。加大对医务人员新冠肺炎防护相关内容的培训,强化督导力度,是提升医院新冠肺炎防控整体水平的有效途径。 相似文献